Some have reached the pinnacle of bodybuilding success with what’s considered bad genetics, such as narrow shoulders, a wide waist and other structural flaws. Sheer determination coupled with a certain degree of savvy, such as knowing how to disguise obvious flaws by highlighting strong points, led to their success.
As science marches on, several gene combinations have been discovered that influence the effects of training programs or vice versa; that is, training can alter gene expression in the body. For example, if you regularly do aerobics, which features fat oxidation, or burning, genes that affect fat oxidation will upgrade in the body after a few workouts. Studies show that the genes for FAT/CD36, a fatty acid transporter, and for CPT-1, an enzyme that works with L-carnitine in promoting fat entry into cellular mitochondria for oxidation, are upgraded by aerobic exercise.
Another gene, one that controls peroxisome proliferative activator receptor-gamma, which promotes fat gains, is depressed by aerobics. Exercise is also known to favorably affect genes related to glucose uptake in muscle. That explains why exercise may help prevent diseases such as diabetes.
In fact, a new study suggests that training programs should match gene patterns for best results.1 It also explains why some people make great gains with high-intensity, low-volume training routines, such as that espoused by the late Mike Mentzer, while others get better results using more volume and higher sets and reps.
At issue are inborn variants of the genes for angiotensin-converting enzyme (ACE). The enzyme is usually associated with blood pressure, since it produces a substance called angiotensin-2, which constricts blood vessels, resulting in higher blood pressure. Variants of the ACE genes affect the way a muscle functions. For example, the D-variant (ACE-DD) favorably affects strength training. If you’re born with it, you have a head start in making rapid bodybuilding gains. That could be an explanation for those who seem to make gains merely by thinking about training.
The ACE-D refers to a deletion of part of the gene, which leads to more ACE being created in the body. ACE is produced in human muscle and is thought to help regulate muscle growth responses. It also has a pathological side, since people who have the variant are also more prone to cardiac hypertrophy, which can lead to cardiac failure in later life. People with the D-variant of ACE show a higher ratio of fast-twitch to slow-twitch muscle fibers, which is more conducive to acquiring greater muscular size and strength. Athletes possessing it excel in sports requiring short-term, high-intensity effort, such as sprint swimming and running.
Another variant of the ACE gene, ACE-2, is associated with greater muscular endurance. Athletes who have it show greater adaption to hypoxia, or lack of oxygen, and have an abundance of slow-twitch muscle fibers, which are suited to higher oxygen intake. Thus, you’d expect champions in sports such as long-distance running to have this variant. From a weight-training point of view, those with the ACE-2 variant would make better progress by using a higher-volume, lower-intensity training system.
In the new study 99 subjects were randomly assigned to three groups: 1) single set, 2) multiple set and 3) control. Both training groups used a periodization system to create variations in training intensity and volume. During the first three weeks they used loads that were 60 to 70 percent of maximum, which permitted an average of 12 to 15 reps per set. For the next three weeks they upgraded to using 70 to 80 percent of maximum weight, with a rep range of eight to 12. For six weeks they trained three times a week, working nine to 11 muscle groups per session, with the single-set group doing one set of each exercise and the multiple-set group doing three.
The subjects were genetically tested at the start. Those with the ACE-2 variant, or the endurance gene, responded best to the multiple-set system using 12 to 15 reps. When doing the slightly heavier eight to 12 reps, however, that group showed no difference in strength.
Those with the ACE-DD variant showed similar gains for both types of loads and systems. They also made the greatest strength gains—and made the same gains no matter how they trained. Still, the DD group made the most gains from the heavier training, implying that they respond best to that kind of weight work.
The ACE-2 subjects responded to the higher reps more favorably because of their inherent endurance capacity. Such people are more likely to also respond to the experimental “hypoxia training,” during which blood vessels are purposely occluded, somehow leading to greater gains in muscle size. People who have the ACE-2 variant get greater tissue oxygenation, which can elevate the contractile properties of heart and skeletal muscle tissue. They would also show less lactate buildup, reflecting reduced muscle fatigue.
It would appear that those who make exceptional gains with high-intensity, heavy training have the ACE-DD variants. They’d gain from just about any type of training program. Those with the ACE-2 variant wouldn’t respond favorably to a workout that features heavy weights and low reps; their physiology is geared toward endurance. For them a program that features multiple sets and a rep range of 12 to 15 per set would produce best results.
From a health perspective, it’s better to have the ACE-2 variant, because, while the ACE-DD leads to bigger muscles, it also has unfavorable effects on cardiovascular factors, such as higher blood pressure and increased heart stress long-term. Thus, with ACE-2 you’ll be smaller but probably live longer.
©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.
